Process for making varnish



' pentine in the Patented Jan. 22, 1929 UNITED srariszs PATENT OFFICE. I

BAILEY F. WILLIAMSON AND WAITER H. IBEISLER, 0F GAINESVILLE, FLORIDA.

rnocEss non MAKING va'mnsn.

R 0 Drawing.

This invention relates to an improved process for making varnish. Theordinary method consists substantially in heating a drying oil, forexample tung oil, with ester gum. Ester gum is commercially prepared byheating ordinary rosin with about 10% of glycerine. The rosin used isprepared in turpentine camps where the theus which exudes from pinetrees is caught 1n a cup hanging on the tree. The crude the us which isa resinoid and always contains more or less foreign matter such aswater, chips and other trash, as well as the rosin, is poured into acopper still where it is heated with direct heat. This causesthevturpentine to be distilled oifand permits the rosin to be drawn offfrom the bottom ofthe still and passed through metal strainers andcotton batting to strain out the foreign matter.

This method of producing rosin tends to partially decompose it andtherefore results in an inferior product. After the I'OSlIl 1s strainedit is poured into barrels in which it is allowed'to cool and harden'sothat it may be shipped to the markets. This shipping ordinarily entailsmuch handling and frequent loss of considerable quantities of rosin,which of course adds greatly to the cost of the finished roduct..

The 0 ject of the present invention is to overcome some of theobjections to the method outlined above, and to produce'a varnish ofhigher quality and lighter color than has heretofore been obtainable.Another oh ect is to provide a process whereby such high quality varnishmay be produced at a comparatively low cost, and a turther ob3ect 1s toprovide meansgwhereby oxidation of them-- gredients is prevented duringthe production of the varnish.

Other objects and advantages will become apparent by reference to thefollowing speclfication wherein we have described our 1mproved process.r

. In carrying out our process we first heat the crude theus sufiicientlyto permit stralning whereby foreign matter- 1s eliminated. The strainedgum theus is then mixed with glycerine and a drying oil, for exampletung oil, and is heated gradually in a still, for a period of aboutthree hours to atemperature of 150 C. This initial heating removes allthe water and distills off part of the turm theus. k The heating iscontinued and a non-oxidiz- Application filed December 30, 1925. SerialNo. 78,356.

ing gas, preferably steam, is bubbled through the mixture until thetemperature reaches approximately 275 C. during which period theremainder of the turpentine and other miscellaneous light or volatileoils in the gum theus are distilled off. The ten'iperature is thenmaintained between 275 and 335 C. for a period of about three hours oruntil the mixture reaches the proper consistency, during which time theflow of non-oxidizing gas is maintained.

\Vhen the mixture reaches the desired consistency, the outside heatingis discontinued but the passage of steam or non-oxidizing gas iscontinued until the temperature drops to about 200 0., at which time asuitable (plan tity of turpentine or other suitable solvent or thinnerand any desired drier is added. The mixture is then permitted to cool sothatit may be packaged and shipped to the user in accordance with commonpractice.

The passage of non-oxidizing gas through the mixture in the still drivesofl the oxygen in the mixture and replaces the air above the mixturewhich would otherwise cause oxidization and consequentlylower thequality of the varnish produced. The passage of this gas also serves tocontinually agitate the contents of the still whereby the use of amechanical agitator becomes unnecessary. The agitation of the mixture bythis means prevents decomposition of the materials due to localoverheating, anda further advantage obtained by the use of gas is foundin the fact that the temperature of the mixture is very'easilycontrolled.

A suitable formula for making varnish according to the above describedprocess is as follows:

Mix 100 parts of strained gum theus, 3 parts of glycerine and 150 partsof tung oil in a still and heat gradually during the period of ahoutthree hours to l50 (1. continue the heating and pass steam through themixtime until the temperature reaches 275 C.'

Maintainv the temperature between 27 5 and 335 C. until the properconsistencyv is obtained when the outside heat should be discontinued,but the passage of steam marn rained until the temperature drops toabout 200 C. Approximately 200 parts of turpentine or other suitablethinner and any desired quantity of drier should be then added and themixture allowed to cool.

We are aware that changes may be made in the formula and methodspecified above, without departing from the essence of the invention andtherefore reserve the right to make all changes which fall within thescope of the following claims.

We claim as ourinvention:

v 1. The improvement in'the art of manufacturing varnish, which consistsin heating a mixture of cl ean gum theus, glycerine and a dryin oilsufiioiently to drive off undesired volati e substances andsimultaneously to combine the glycerine with the rosin content of thetheus to form the desired gum constituent and incidentally to combinesaid gum constituent with the drying oil constituent so as to 'form thevarnish base.

' 2. The improvement in the art of manufacturingvarnish, which consistsin heating a mixture of clean gum theus glycerine and tung oilsufliciently to drive oil undesired'volatile substances andsimultaneously to combine the glycerine with the rosin content of thetheus to form the desired gum constituent and incidentally to combinesaid gum constituent with the tung oil constituent so as to form thevarnish base. i

'3. The cess of making varnish which consists 0 heating together gumtheus, glycerine and tungoil in a still at a relatively low temperaturewhereby the water and part only of the turpentine aredistilledout,continuing the heating at a higher temperature whereby the'remainingturpentine is distilled out and until-the desired consistency of theheated mass is obtained, and then cooling and adding the desiredthinner.

4. The process ofmaking varnish which consists in heating together gumtheus, glycerine land tung oil in a still to a temperature of about 150C. until the'water and part of the turpentine aredistilledqoutcontinuing the heating at a temperature of substantially 275 C. untilthe remainder of the turpentine in the gum theus is distilled out,maintaining a temperature between 275 and 335 C. until the mixturereaches the desired consistency,

coolir ilg, and thereafter addingthinner.

5. he recess of making varnish which consists o mixing substantially 100parts of gum theus, 3 arts of glycerine and 150 parts of tung oil,eating ,the mixture gradually to'a temperature of approximately 150 Cduring aperiod of substantially three hours raising the temperature toapproximately? 275 (3., and maintaining the temperature be-' tween 275and 335 (l'until the mixture is'of 1 the desired cons'istency.

'6. :Iheproce'ssofmaking varnish whichcons sts in mixing gum theus,glycerine and tun 011 in proportions of substantially 100, 3 and 150respectively, heating the mixture radually in a still to approximately150 until t e gum theus is converted to ester gum, continuing theheating and passing steam through the mixture until the temperaturereaches substantially 275 (1,v maintaining consists of heating togethergum theus, glyc-- erine, and a drying oil in a still to a temperaturewhereby the water andpart of the turpentine are distilled out,continuing the heating, and passing a non-oxidizinggas through themixture until the remainder of the turpentine is distilled out and untilthe des red consistency of the mixture is obtained.

8. The process. of making varnish which consists ofheating together'gumtheus, glycerine, and tung oil in a still to a temperature whereby thewater-and part of the turpentine are distilled out, continuing theheating and passing steam through the mixture until out and untilthedesired consistency of the mixture is. obtained.

9, The improvement in the art 'of manufacturing varnlsh which consistsin heating a mixture of clean gum theus, lycerine and a the remainder ofthe turpentine is distilled drying .oil in proportion of su stantially100,

3 and 150 respectively, sufliciently to drive off undesired volatilesubstances and simultaneously to combine the glycerine with the rosincontent of the theus to form the desired gum constituent andincidentally to combine said gum constituent with the drying oil so asto form the varnish base. 7

10. The improvement in the art of manufacturing varnish, which consistsin heatin a mixture of clean gum theus, glycerine an a drying oilsufliciently to drive off undesired volatile substances andsimultaneously to combine the glycerine with the rosin content;

of the theus to form the desired gum constituent and incidentally tocombine said gum con stituent with the drying oil constituent so as v toform theyarnishbase and bubbling a nonoxidizin gas through "the mixtureduring part of t e time it is so heated.

11. The improvement in the art of manufacturing varnish, which consistsin heatin a mixture ofclean gum'theus, glycerine an a dr ing oilsufliciently to drive off undesired v0 atile substances andsir'iiultaneously to "combine the glycerine with the rosin content ofthe theus to form the desired gum constituent and incidentally tocombine said gum constituent with the dr ing oil constituent so as toform the varnish ase and bubbling a nonoxidizing gas v through themixture during part of the time it is so heated thereby producing avarnish of very light color.

12. The process of making varnish, which consists of mixing together,gum theus, glycerine anda drying oil, heating the mixture graduallyduring a period of about three Lemma hours to a temperature ofapproximately 150 0., raising the temperature to approximately 275 (3.,and maintainin the temperature between 275 and 335 (3, until the mixturereaches a consistency where a cooled portion thereof can be drawn intofine threads 13. The improvement in the process of making varnish whichconsists in combining the rosin content of gum theus with glycerine anda drying oil in one operation by heating a mixture of gum theus,glycerine, and a drying oil together in a still, and passing steamthrough the mixture, While heating it, to agitate the mixture and tofacilitate chemical action by the presence of moisture.

, 14:. The improvement in the process of making varnishjwhioh consistsin combining the rosin content of gum theus with glycerine and a dryingoil in one operation by heating such gum theus, glycerine and drying oiltogether in a still so that. the turpentine and light oil contentofthegum theus is driven ofli' as an incident to the process.

BAILEY F. WILLIAMSON. WALTER BEISLER. i,

